An endocutter is a surgical tool that staples and cuts tissue to transect that tissue while leaving the cut ends hemostatic. An endocutter is small enough in diameter for use in minimally invasive surgery, where access to a surgical site is obtained through a trocar, port, or small incision in the body. A linear cutter is a larger version of an endocutter, and is used to transect portions of the gastrointestinal tract. A typical endocutter receives at its distal end a disposable single-use cartridge with several rows of staples, and includes an anvil opposed to the cartridge. The surgeon inserts the endocutter through a trocar or other port or incision in the body, orients the end of the endocutter around the tissue to be transected, and compresses the anvil and cartridge together to clamp the tissue. Then, a row or rows of staples are deployed on either side of the transection line, and a blade is advanced along the transection line to divide the tissue. Traditionally, it has been important to maintain a substantially constant gap between the anvil and the cartridge for proper staple formation. A staple urged outward from the cartridge or other staple holder is designed to encounter a staple pocket or other feature in the anvil at a certain point in its travel. If the staple encounters that staple pocket or other feature in the anvil too soon or too late, the staple may be malformed. For example, if the gap is too large, the staple may not be completely formed. As another example, if the gap is too small, the staple may be crushed.
The use of the same reference symbols in different figures indicates similar or identical items.